661166166116 has 24 divisors (see below), whose sum is σ = 1160460255864. Its totient is φ = 329606323200.

The previous prime is 661166166061. The next prime is 661166166121. The reversal of 661166166116 is 611661661166.

It can be written as a sum of positive squares in 4 ways, for example, as 250746556516 + 410419609600 = 500746^2 + 640640^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13956566 + ... + 14003858.

It is an arithmetic number, because the mean of its divisors is an integer number (48352510661).

Almost surely, 2^661166166116 is an apocalyptic number.

It is an amenable number.

661166166116 is a deficient number, since it is larger than the sum of its proper divisors (499294089748).

661166166116 is a wasteful number, since it uses less digits than its factorization.

661166166116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57551 (or 57549 counting only the distinct ones).

The product of its digits is 279936, while the sum is 47.

The spelling of 661166166116 in words is "six hundred sixty-one billion, one hundred sixty-six million, one hundred sixty-six thousand, one hundred sixteen".